Standard 1D proton NMR spectrum of carbohydrates exhibit recognizable signals for anomeric protons and a few other sites in special cases. The remaining sugar proton resonances are grouped together to form an unresolved envelope. COSY spectra can be used to recognize and assign the individual resonances in these enveloping signal clusters. The interresidue linkage and overall sequence of carbohydrates can be analyzed by a NOESY spectrum. The compounds to be analyzed are a mixture of cyclopolygalacturonic acids with ring sizes of 5,6,7, and 8. These compounds are similar to ?-, ?-, ?-cyclodextrins with a molecular weight of 900-1400 Da. The possible structure may be a-1,2 or a-1,4 glycosidic linkage. COSY spectra will be used to assign the proton resonance for each sugar ring, and symmetric off-diagonal NOE crosspeaks may help to determine the interresidue linkage. If there is a crosspeak between H1 and H2 or H1 and H4 on two connecting sugar rings, then the glycosydic linkage can be clearly assigned.